Lotus 79 construction report – part 5

Manufacturing the clutch-gearbox unit

Today, an update on the manufacturing of the clutch-gearbox housing of the Lotus 79 (built in 2010).

Lotus had a bit of a chaos with their gearboxes at the beginning of the 1978 season. Usually they used “Mike Hewlands bunch of old rickety gears ” as Colin Chapman liked to describe the Hewland gearboxes. His antipathy to Mike Hewland did not come from nowhere. His Hobby was, to tinker around on race gearboxes. So it came, that Lotus and Getrag developed a gearbox for the 79. Even if Lotus used it at the prototype 79/1, it was never used in races as it was to weak for F1 cars.

As they raced with the Hewland FG gearbox, they experimented around at the back end of the gearbox and also developed a clutch-oiltank housing addition to the gearbox.

On hewland.com you can download the gearbox manual and installation drawings.

The gearbox housing. You can see the inboard brakes and spring-damper unit.

The oil coolers at the left hand side of the monocoque. The upper one is for the gearbox oil (not connected yet), the lower on is for the engine oil cooling.

The housing which contains the clutch and oil tank was a Lotus developed part. Here you can see the rear of the engine with the flanged housing. The small cylinder you can see at the housing is the clutch activation.

At the left hand side of the clutch-oil tank housing, the compressed air starter is mounted. At the top of the housing you can see the catch tank.

Full gearbox unit with mounted frame for the suspension elements.